Homebrew PCBs

A number of years ago, I had done some rough calculations and a 
bit of empirical testing (which turned out mostly unsatisfactorily), 
involving electrolytically regenerating spent Ferric Chloride 
solution.  My approach involved electrolytically depositing the 
Copper out of the solution, and replacing it with Iron.  The
electrolytic deposition of the Copper did work (I ended up with
some beautiful looking "Copper trees".), and the Iron anode
did dissolve.  There was little (if any) Chlorine gas evolved.
But, I'm not real sure that the Iron that was dissolved formed
Ferric Chloride, or some other allotrope (e.g., Ferrous Chloride, 
etc.).  However, it may be worthy of further study.

Note that one of the problems with etching Copper with Ferric 
Chloride solution is that the result is a Copper Chloride, as well
as a Ferric Hydroxide (that brown, muddy looking stuff).  The
Ferric Hydroxide has to be removed from the active area of etching,
or it'll clog up the etching process.

http://en.wikipedia.org/wiki/Ferric_hydroxide

Theoretically, the Ferric Hydroxide could be filtered out of
spent solution.  Maybe.  

As for suspending boards, based on personal experience, Mylon is 
no good, since the Ferric Chloride will attack it.  For that matter,
Chlorine attacks a LOT of things.  PVC, or PVDC, should be fairly
good, since those have quite a few Chlorine atoms on the chain 
already.

Dave